The present invention relates an improved stopper structure for a storage battery centainer, which includes a plurality of stopper supports for plugging into the predetermined openings provided on the container, such that the water vapor is not permitted to escape through the openings, hence, the amount of fluid in storage battery is always kept constant and therefore, the trouble of adding storage battery fluid is avoided.
Referring to FIG. 5, there is shown a perspective view of a prior art device. The stoppers of such prior art device are each of a hollow, cylindrical shaped stopper, which can plug exactly into the openings of the battery container. When in operation, gas will evolve and may escape, with water vapor, through the stopper, therefore, more battery fluid should be added through the openings. Over extended periods of time, if battery fluid is not replenished in such case, the lead plates of storage battery will be sulfurized and damaged, which means that the longevity of the battery will be minimized or more distilled water should be added, and naturally, it is very troublesome. This is due to the pre-determined openings provided on the container and there is no means to block the passage for gas evolved.